The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 24, 1987
Filed:
Jul. 16, 1984
Terence A Benge, Farringdon, GB;
Cyril M Prince, Witney, GB;
Metal Box Public Limited Company, Reading, GB;
Abstract
A multilayer plastics sheet destined to be formed into foodstuff containers by thermoforming has a barrier layer for low oxygen permeability, and incorporates reclaim material for providing desired mechanical properties to the sheet. The reclaim material represents 40-60% of the sheet by volume, and in order to incorporate these high reclaim levels without concomitant organoleptic problems the reclaim material is formed as a single layer adjacent what is to be the outside surface of the container. The sheet is accordingly highly asymmetric, but any substantial polymer melt instability during coextrusion tending to cause layer thickness variation and lack of visual appeal of the sheet is prevented by forming the sheet as two substantially symmetrical components which are individually and separately coextruded, and subsequently extrusion laminated together. Of the components one includes, and is symmetrical in relation to, the barrier layer, and the other likewise incorporates the reclaim layer.